feedback – Qs Mark Scheme Exam Report

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Restless Earth
1 (a) Describe the characteristics of oceanic
crust. (3)
• Oceanic crust is generally less than 200 million years old – some is
much newer – a million years old in Iceland. It is dense and can sink
beneath continental crust. Oceanic crust can be renewed at
constructive plate margins and destroyed at subduction zones. The
characteristics may be described in a comparative way with reference
to continental crust.
• 3 x 1 per basic point, 1 + 1 per elaborated point
1 (a) Exam Report
• Many gained maximum marks in 1(a) by noting the age of oceanic
crust, the fact that it can be renewed or destroyed and its density.
Some did this in a comparative context with regard to continental
crust although there was no requirement to do so. Basic answers
merely listed, such as saying that it was young, thin and dense.
1 (b) Study Figure 1 on the insert, a map showing the world
distribution of volcanoes. Describe the world distribution of
volcanoes. [3 marks]
1 (b) Study Figure 1 on the insert, a map showing the world
distribution of volcanoes. Describe the world distribution of
volcanoes. [3 marks]
• Volcanoes occur in lines, such as along the west coast of North and
South America. There are many clustering along the edge of the
Pacific Ocean, especially in/near Japan. There are small clusters in
places such as Iceland, southern Italy. They tend to follow the plate
margins such as in the middle of the Atlantic Ocean where the plates
are moving apart or near Japan where the plates are moving together.
This is not always the case and some such as Hawaii are a long way
from plate margins and occur relatively isolated.
• 3 x 1 per basic point. (1 +1) +1 if one point elaborated.
1 (b) Exam Report
• The concept of distribution was poorly understood in 1(b). Many
recognised the spread around plate margins. However, many then
drifted onto location, rather than distribution. There is a need to
engage with the appropriate language, noting the clustering in areas
such as around the Pacific plate/the ‘Ring of Fire’. Where candidates
could do this, they quickly gained the three marks available – often
noting anomalies, such as the volcano in the middle of the Pacific
Ocean. Some mistakenly and irrelevantly began to explain reasons
volcanoes were found at plate margins.
Study Figure 2 on the insert, a photograph of Eyjafjallajökull, a volcano in
Iceland.
1 (c) (i) Draw a labelled sketch cross section to show the characteristics of
this volcano. [3 marks]
Study Figure 2 on the insert, a photograph of Eyjafjallajökull, a volcano in
Iceland.
1 (c) (i) Draw a labelled sketch cross section to show the characteristics of
this volcano. [3 marks]
• Cross section should clearly replicate the outline shape of the volcano
visible in Figure 2 – the horizon line should be recognisable - 1 mark.
• Labels are likely to describe the relatively low height volcano, the flat
top, gently sloping sides, may note that it is snow covered near the
top and that it has the shape of a shield volcano - 2 marks for labels
that must be arrowed and make contact with the feature being
described.
• Only labels pointing to the horizon line are permissible and reference
to wide base is only permissible if there is an appropriate sketch cross
section. Textbook style diagrams showing internal structure are not
permissible – but marks can be given for appropriate labels.
1 (c) (i) Exam Report
• In 1(c)(i), there was a need to use the photograph in Figure 2 to draw
the sketch profile of the volcano. As with a cross section drawn using
an OS map, a single line showing the shape of the volcano was all that
was required. However, many disregarded the photograph and drew a
textbook cross section showing the internal structure of the volcano,
which was clearly not visible on the photograph. Where an
appropriate profile was drawn, many lost marks by not connecting
the arrow to the feature referred to or by labelling gentle slopes when
the line drawn depicted the opposite. There were some very good
responses where the outline shape was drawn and the labels applied
were appropriate but these were all too rare.
1 (c) (ii) Use a case study to discuss the immediate and long-term
responses to a volcanic eruption. [8 marks]
Level 1 Basic (1 – 4 marks)
Likely to consider either immediate or long term
responses only or not distinguish between these.
Responses will be generic – even if a case study is given.
Statements are simple and separate in a random order.
Level 2 Clear (5 – 6 marks)
Immediate and/or long term responses are considered.
There is some specific reference to the named case
study.
Statements are developed and linked – begins to
discuss.
Level 3 Detailed (7 – 8
marks)
Immediate and long term
responses are considered.
There is specific reference
to the named case study.
Statements are developed,
linked and logically
ordered.
Discussion is clear .
1 (c) (ii) exam report
• Specific case study material was needed in 1(c)(ii). Popular choices were
Mt St Helens, Soufriere Hills volcano and Eyjafjallajokull but the naming of
the case study alone was not adequate to progress through the levels.
There had to be specific locations, events etc that made direct use of the
example, rather than naming it and then giving generic information. Some
did use more than one, in which case their efforts were diluted and the
better one credited. Those who did describe the specific immediate and
long term responses accessed level 2 often with a hint of
analysis/comment that constituted discussion. There was a need to engage
more fully with the command word to get to Level 3 commenting on how
the strategies worked and how effective they were. Thus, recognising the
evacuation of 800 people in southern Iceland from Eyjafjallajokull as a
result of the ash and the impact on people, causing choking, was indicative
of the necessary discussion.
1 (d) (i)
• Description that reflects shape –
idea that it is rounded, circular
although not perfect/oval.
58-62 km
1 (d) (i) exam report
• Generally 1(d)(i) was well done with measurements being accurate
and the shape clearly described.
1 (d) (ii) How is a supervolcano different from
a volcano? (comparison Q)
• A supervolcano is much bigger than a volcano – in terms of
its base/shape and the amount of magma that is erupted –
where at least 1000 cubic km of material can be erupted – in
contrast to Mount St Helens where 1 cubic km was erupted.
It is different in shape as it is sunken in the middle rather
than coming to a peak. Supervolcanoes erupt less frequently.
• Can refer to two basic differences or one that is elaborated
with regard to size, shape, amount of material erupted.
1 (d) (ii) exam report
• In 1(d)(ii), differences had to be established to obtain the marks.
Description of the supervolcano did not answer the question asked.
Thus, marks were awarded when differences were established such as
the presence of a cone versus a caldera or the recognition that a
supervolcano is much bigger.
1 (d) (iii) Describe the likely global
consequences of a supervolcano eruption. (4)
• Likely global consequences are the impact of the ash that would be
emitted into the atmosphere. This would travel away from the
volcano with the wind towards countries like the UK where it would
be expected to arrive within 5 days of an eruption. The ash would
reduce the amount of rays from the Sun that could penetrate and so
temperatures would fall – causing a volcanic winter. This would make
it difficult to grow enough food, crops would fail and it could lead to
widespread deaths and people trying to emigrate.
• Level 1 Basic (1 – 2 marks)
• Describes consequences of a supervolcano eruption – may drift to
local/national.
• Statements are general and separate in a random order.
• A huge amount of ash will go into the air. It will come back to the ground. Some
will get to other countries and it can affect temperature.
• Level 2 Clear (3 – 4 marks)
• There is clear reference to the global consequences of a supervolcano eruption.
• Statements are developed and linked – focus on effects.
• A huge amount of ash will be erupted into the atmosphere. This will travel
around the world. It will reduce the amount of sunlight reaching the Earth’s
surface and so temperatures will fall. This cooling will cause a volcanic winter. It
will have serious effects on what crops we can grow and food shortages are
likely to result.
1 (d) (iii) exam report
• There was a need to have both a global focus – going beyond stating
the word global – and some sequence and/or development in
statements in 1(d)(iii). For example, random references to ash and its
impacts, planes and crops was a Level 1 response whilst recognising
that ash from Yellowstone in USA would cut out sunlight in places
including the UK and the impact this would have on photosynthesis,
crop growth and food supplies constituted a level 2 response. Some
were extreme in the impacts noted indicating that everything would
be destroyed whilst others used Yellowstone but looked at the impact
on USA only.
Water on the Land
First 3 questions…
• 5 Water on the Land
• 5 (a) Study Figure 13 on the insert, a 1:25 000 Ordnance Survey map
extract of part of the Peak District.
Damflask Reservoir is named in grid square 2790. The dam is in grid square
2890.
• 5 (a) (i) What is the length of the dam along the line X–Y on the map? [1
mark]
.................. km
• 5 (a) (ii) What shape is Damflask Reservoir? [1 mark]
• 5 (a) (iii) Describe the relief (height and slope of the land) around Damflask
Reservoir. [2 marks]
5 (a) (i, ii and iii)
i. 0.25 – 0.30km
ii. Wedge shaped/wider at south eastern end and tapers north
west/long and thin/triangular.
iii. Land immediately next to reservoir is about 170m, rising to over
300m; land is higher on north side. Slopes are steep/very steep at
Firs Hill/less steep near eastern end at Dungworth.
1 for height and 1 for slope. 2 x 1.
5 (a) (i, ii and iii) Exam Report
• The vast majority identified the correct distance in 5(a)(i), whilst in 5(a)(ii)
there was a need to convey the shape in a way that would give the reader a
clear impression of what the shape was. Thus, answers such as Nike sign,
elongated foot shape, triangular (which was a popular choice), cone –
shaped were accepted and, more conventionally, indicating that it was
narrow but widened near the dam – in the latter case there had to be
reference to specific area where it widened. This proved more difficult than
the shape of the caldera in question 1. Responses to 5(a)(iii) were often
vague and imprecise. There was a misconception that the slope was gentle
and often there was no specific height – where this was present, there had
to be units given. The quality was poor and basic mapskills weak – an area
to work on as candidates should have been able to recognise the close
spacing of the contours and identify a specific height in close proximity to
the reservoir.
5 (b)
Study Figures 14a and 14b on the insert, maps showing rainfall (2012)
and population density (2011) in England and Wales.
Explain how Figures 14a and 14b show that there are likely to be areas of
water surplus and areas of water deficit in England and Wales.
[6 marks]
5 (b) mark scheme
• Level 1 Basic (1 – 4 marks)
• Some description of the maps – likely to be separate.
• Begins to link to either water surplus or deficit at the top end – likely to be
implicit
• Statements are simple and separate in a random order.
• Level 2 Clear (5 – 6 marks)
• There is description of the maps which are used to illustrate areas of water
surplus and water deficit.
• Specific evidence quoted from the maps.
• Statements are developed and linked.
5 (b) mark scheme
• The maps indicate a reduction in rainfall from west to east – with many areas
of Wales and the Lake District receiving in excess of 1500mm and even higher.
This is in contrast with 800 – 1000mm in central areas including the Midlands
and less in East Anglia and Greater London and Kent. The population density
shows low levels in Wales – 0 – 99 per sq km indicating that this would be an
area of water surplus – as there are relatively few people and a lot of rainfall.
Conversely, in London, densities are in excess of 1000 per sq km and often
5000 and 10000. Yet here rainfall totals are much less suggesting that there
will not be enough water to satisfy the needs of the population – and
therefore indicating an area of water deficit.
• There are other valid examples – but these are perhaps the most apparent –
any example from the map is valid – but they must illustrate water surplus
and water deficit rather than instances where this may not be apparent.
5 (b) exam report
• Responses to 5(b) were often clearly focused on the two maps, made
effective use of the resources and quoted evidence in support to
illustrate the concepts of water surplus and water deficit. This was
overall well answered; the lack of use of evidence often prevented
progression to Level 2. A limited number confused west and east
which had a detrimental impact on the answer and some did
disregard the data – but this was a limited number in this question.
5 (c) (i) On Figure 16, mark with an arrow and label three
characteristics of the waterfall.
[3 marks]
• Any valid label such as stepped profile of waterfall, the fact that river
veers to left above waterfall, has clearly downcut bed here more,
white water, plunge pool, undercutting of the lower rock layer, the
presence of two rock layers, hard rock and soft rock both correctly
labelled for 1 mark. No credit for waterfall only.
• Arrow must touch specific feature for credit.
5 c (i)
• As with other questions necessitating the labelling of a diagram, map
or photo, candidates had to be accurate in the ending of the arrow,
ensuring it matched what was visible at one end and the written label
at the other. Often, candidates didn’t connect the arrow, plunge pool
was frequently inaccurate being in the foreground of the picture, and
missed the obvious – it was rare to see the stepped profile noted or
even the white water. There was a clear need to focus on what was
visible and the waterfall as demanded by the question.
5 (c) (ii) Explain the formation of a waterfall. (4)
• Likely explanation will refer to horizontal bands of hard rock and soft
rock; hard rock will form cap rock with underlying band of soft rock
exposed; erosion of softer rock at a faster rate causes an overhang to
develop; abrasion and hydraulic action are particularly important
erosion processes; material from overhang collapsing increases rate
of erosion and waterfall plunges over steep drop created.
• Diagrams if included should be credited as an integral part of the
answer.
• Level 1 Basic (1 – 2 marks)
• Simple points - partial sequence.
• Statements are separate in a random order – jumps about/sequence not
correct.
• River erodes rock downwards. There is hard and soft rock. The overhang
collapses and the water flows down a steep drop.
• Level 2 Clear (3– 4 marks)
• Complete, clear sequence.
• Statements are developed and linked in a logical order.
• There are layers of horizontal rock. Hard rock is on top of soft. Where the soft
is on the surface next to the hard, it is eroded faster by abrasion and hydraulic
action and an overhang is created of the cap rock. Over time, this gets bigger
and eventually it collapses creating a waterfall. Repeated erosion by material
in the plunge pool deepens the waterfall.
5 c (ii) exam report
• Responses to 5(c)(ii) were varied – at one extreme were those who did not
refer to rock types or who had the orientation incorrect and had vague
ideas about erosion. At the other end of the scale, there were clear
sequences noting the horizontal alignment of rocks, with the hard rock as
the cap rock. They began with a relatively gentle slope and explained the
sequence and processes, such as abrasion and undercutting that led to the
steepening of the profile to form the waterfall. A significant number drew
diagrams to support their explanation. For some, this clarified confusion
where soft rock was on top of and in front of hard rock or the waterfall was
present at the start and the explanation focused on the gorge of recession.
For others, there was a clear sequence that complemented the text and
aided the written explanation given.
5 (d) Describe how river processes of transportation and
deposition change downstream. [8 marks]
• Reference may be made to transportation processes, size of material that is carried and deposition,
where there should be reference to load size and amount that is deposited and where it is
deposited.
• The emphasis should be on change downstream. Traction – the rolling of the largest material - and
saltation – the bouncing along the bed of stones and pebbles – should be seen as occurring nearer
the source as the load is larger there. In contrast, the load carried by suspension – where fine silts
and clays float within the body of the river – is more apparent in the lower course as the material is
smaller here. The river will be carrying much greater quantities of material here than nearer the
source as it has more water present. Solution will vary with the rock type and may not relate to
distance from the source but whether there is soluble rock present within the drainage basin.
• Deposition occurs anywhere along the river’s length – but nearer the source, it is large material
that is left behind. Often huge boulders that stick out above the level of the water can be found,
reducing in size with increasing distance from the source. The amount deposited increases
downstream – but this is increasingly fine sediment. This may be deposited on flood plains lower
down whereas these are not present in the upper course. Meanders which are present in middle
and lower course show contrasts in deposition from one side to the other with little on the outside
bank and much on the inside bend of the meander.
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Level 1 Basic (1 – 4 marks)
Some description of the way(s) in which the river transports material and/or deposits it.
Statements are simple and separate in a random order.
A river deposits big material first and carries smaller load further. It carries material by rolling boulders, bouncing
stones and dissolving some rocks. Material is deposited on the inside bend of a meander.
Level 2 Clear (5 – 6 marks)
There is description of transportation and deposition – although there may be imbalance.
Statements are developed and linked – begins to focus on changes downstream.
Large material is rolled along the river bed. This process of traction occurs near the source and gets less as you go
downstream. The same is true of saltation where smaller stones hop along the river bed. However, suspension –
where silt is carried within the river floating in the water increases downstream. Near the source, material is found
across the channel but further down, material is left on one bend of a meander only.
Level 3 Detailed (7 – 8 marks)
There is detailed description of transportation and deposition – in reasonable balance.
Statements are developed, linked and logically ordered – clearly focuses on changes downstream.
Describes how river processes of transportation and deposition change downstream.
In the upper course, much material is transported by traction and saltation. Large boulders are rolled along the
river bed and smaller stones bounce along it. This gets less as the load size reduces downstream. However,
suspension where fine silts and clays are carried within the river’s water increases in the middle and lower course
and this takes over as the main way of transporting the load as it is now much smaller. The large load is deposited
in the upper course but this is replaced by silts and clays downstream – smaller in size but a larger amount is left
behind. In the upper course, large boulders are strewn across the channel often above the water level, but
downstream where meanders are present, deposition occurs on the inside bed particularly rather than all the way
across the channel.
5 (d) exam report
• There were a number of aspects to consider in 5(d). However, the execution
of this question was less effective. There was a need to understand the
different transportation processes and to be aware of the amount and size of
load being left behind, and then to demonstrate changes downstream. Some
were confused by specific transportation processes, giving terms but
incorrect definitions. Many could describe the transportation processes but
failed to link to changes downstream. Deposition was the major discriminator
as candidates focused on this to a lesser extent. Some drifted to erosion
and/or explanation. The best looked at upper, middle and lower course and
described which transportation processes were dominant in the different
sections and were aware of largest load being left behind at the source, with
greater quantities of smaller material nearer the mouth. There was significant
confusion on velocity and how it changed and this had a negative impact on
the understanding of the transportation and deposition processes which were
a focus of the question.
The Coastal Zone
7 (a) Study Figure 21 on the insert, a photograph of
Happisburgh, Norfolk.
Outline the evidence from Figure 21 that suggests erosion
is taking place on this coast. [3 marks]
There is much evidence that suggests that erosion is occurring.
The caravan is very near to the cliff edge and there are a number
of empty pitches marking areas where other caravans once stood
but have had to be moved back from the coast. The road near the
remaining caravan is very near the edge. The cliffs appear
unstable – there is grass part way down in the centre and
vegetation overhanging at the top; the toe of the cliff shows
evidence of material having fallen and the vertical section near the
top indicates further evidence. On the beach itself, there are the
remains of earlier coastal defences where the original posts
remain, but much of the middle sections have been removed.
Groynes are present showing an attempt to prevent longshore drift
3 x 1 per simple point or 1x (1+1) for a developed point + 1.
7 (a) exam report
• As with many of the other photograph-based questions, there was a
need to look at Figure 21 in 7(a) and then respond to the question.
There was plenty in the photograph that indicated erosion but not all
appeared clued into the question. Where candidates did engage with
the question, many noted the presence of groynes and revetments
(not sea walls) and the fact that they were now only partial, some
saw the cliff profile and the evidence of slumping via the material at
the ‘toe’, whilst others recognised that the caravans had been moved
away or would not have been pitched so near to the coast initially.
Some did call these houses.
7 (b) Explain the formation of a wave-cut platform.
[4 marks]
• Explanation will refer to waves hitting the base of the cliffs between
the high and low water mark. This will lead to erosion of the base by
such processes as hydraulic power and abrasion. This will result in
undercutting and an overhang will develop above. Over time, the
overhang will get bigger and a critical point will be reached when it
cannot support itself. It will then collapse, leading to the retreat of
the cliff face. As this repeats, a wave-cut platform is left where the
cliff used to extend out to sea.
• Diagrams if included should be credited as an integral part of the
answer.
• Level 1 Basic (1 – 2 marks)
• Simple points - partial sequence.
• Statements are separate in a random order – jumps about/sequence not correct.
• Waves attack the cliffs. They lead to undercutting and rock collapses. The cliffs go
backwards. A wave-cut platform is a gentle slope.
• Level 2 Clear (3– 4 marks)
• Complete, clear sequence.
• Statements are developed and linked in a logical order.
• Waves hit the base of the cliffs between the high and low tide levels. This leads to
erosion of the base of the cliffs as they are pounded by waves and rocks and
pebbles are hurled at the cliffs. These processes lead to undercutting. As erosion
continues, an overhang develops and increases in size. At some point this will not
be able to support itself and it will collapse. The process will occur again and over
time a wave-cut platform will be formed – and get bigger as the cliffs retreat,
leaving the wave-cut platform in their place.
7 (b) exam report
• Some weaker candidates saw a wave-cut platform in 7(b) as a result
of the build-up of material, rather than a product of erosion. Some
seemed to be unaware of the landform and just guessed and there
was quite a common misconception that there was soft rock at the
base of the cliffs and hard rock on top. However, there were a
significant number of clear and sequential explanations, many of
whom also referred to valid processes, ending with the retreat of the
cliff revealing the wave-cut platform where the cliff had once stood.
7 (c)
• The selection does not matter; it is the justification which must be
considered. There should be reference to the advantages of the
chosen strategy and the disadvantages of the two that have been
rejected. There is likely to be reference to cost, the length of time
they last, their effectiveness, their visual impact, their impact on the
coastal system and habitats; their impact on the economy – especially
with regard to tourism.
Level 1 Basic (1 – 4 marks)
• Simple advantages of chosen strategy and/or disadvantages of those rejected are considered.
• Begins to consider why the strategy selected is best option.
• Statements may be in a random order.
• The sea wall is the best option. This lasts the longest. It lasts at least 3 times longer than the other two. This will
make it worth the extra money spent as it will stop the sea from eroding the coast. The cheaper methods are
not as effective. People will not feel safe and think they are a waste of money.
• Level 2 Clear (5 – 6 marks)
• Advantages of chosen strategy are clear and/or disadvantages of those rejected.
• Purposeful justification– makes a case for chosen option.
• Statements are developed and linked – with clear reference to information not present in table.
• The sea wall will last at least 3 times longer than the other two strategies. This will make the extra money spent
worthwhile as it will require less maintenance. People will feel more secure and businesses will continue to
invest in seaside resorts knowing that they have so many years protection. The top of the sea wall usually has a
promenade built on top of it – further encouraging tourists as they can walk along the sea front. The sea wall
does not interfere with coastal processes like groynes do. They do not stop the movement of material along the
beach and starve other areas of sand. The rock armour is more obvious than the sea wall as huge boulders of
rock types different to that locally are placed at the foot of cliffs and these are unsightly – detracting from the
appearance of the area.
7 (d) exam report
• There was a need to use both the information in Figure 22 and own
knowledge to put forward an argument as to why the strategy
selected was the best choice. Those who relied on the table only
often put together a coherent response which focused on the
positives of the strategy selected and perhaps also the negatives of
those rejected. Own knowledge manifested itself with regard to how
the strategies worked and/or their impacts regarding providing access
and a promenade in the case of a sea wall, or having an impact on
longshore drift and deposition along the coast in the case of groynes.
The best sought to competently make a case for their selection.
• 7 (d) (i)
2524 [1 mark]
• 7 (d) (ii) 2km [1 mark]
• 7 (d) (iii) This is an area of large mud deposits. It is
marshy/saltmarsh in places such as in the west. There are many small
islands and inlets/creeks and some small streams flow across the
mud. It is flat, below 10m and is tidal.
• 2x1
7 (d) (i-iii) exam report
Most gave the correct 4 figure reference for 7(d)(i) – a 6 figure
one was incorrect as the question did not ask for this. Similarly,
most identified the correct distance in 7(d)(ii), although there
was some confusion over the scale. Responses to 7(d)(iii)
were variable with the best using the key and identifying the
flat, low lying marshy area. Others wrongly noted cliffs and
features of the land, rather than the coast.
7 (e) Use a case study of a coastal habitat to describe how
it has been conserved and discuss how this has led to
conflict with other land uses. [8 marks]
Level 1 Basic (1 – 4 marks)
Outlines how area has been conserved and/or conflict present – may be list-like at
lower end.
Statements may be in a random order.
Simple points which are recognisable/applicable to stated environment.
Information is general.
Level 2 Clear (5 – 6 marks)
Clearly describes how area has been conserved and conflict present - there may
be significant imbalance between the two parts.
Statements are linked and developed – begins to link conservation to resulting
conflict – begins to discuss.
Case study is clearly used.
Level 3 Detailed (7 – 8 marks)
Clearly describes how area has been conserved and conflict present - in reasonable
balance.
Statements are developed and linked – purposefully links conservation to ensuing conflict
– clear discussion in this context.
There is detailed, specific reference to the case study.
7 (e) exam report
• 7(e) was often poorly done but there was evidence that candidates could
either engage with the question or not. Many did not understand the
concept of a ‘coastal habitat’. Many saw the question as relating to coastal
erosion and management and launched into coastal protection in areas
such as Holderness which did not answer the question. Some could
describe strategies having named an appropriate area, although
information such as providing boardwalks and noticeboards was included
in a generic fashion. There was a need to refer to specific locations, species
and problems. Where there was specific information, candidates still had
to address the question with regard to how the conservation measures led
to conflict between different users. This often led to farmers, people
visiting for recreation and where this connection was made and support
given, there were some very good discursive answers.
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